Mario's Instructor Quiz

[iacas]

It reminded me (before I watched it) of this: http://thesandtrap.com/b/playing_tips/the_instructor_quiz_nine_questions_youve_gotta_ask. But it's a bit simpler in reality.

Watch the questions, as he says more than I'm willing to type, but typed out the questions are:

1. When the golf club hits the golf ball, what's required for the ball to go up in the air?
2. In a properly struck golf shot, what does the divot tell you?
3. What primarily determines the starting direction of the golf ball?
4. Can you actually compress a golf ball?
5. Why is it easier to curve a 4-iron than a sand wedge?
6. What makes a golf ball break?
7. How do you increase backspin on a shot? What has to actually happen?
8. If you look at any PGA Tour range, almost everyone has a different style of grip, posture, alignment, etc. How are they fundamentals?
9. At what point in the swing do the hands reach their lowest point?
10. With a driver, why does hitting up actually make the ball go farther?

The first person to answer all of the questions correctly (and explain each of them) will win a TST custom ball marker from Mike. Mike and I will be the sole judges as to what the correct answers are (and I can tell you that we probably disagree with Mario on one of them, but we know what he meant to ask... :D), and possibly another one too.

Be specific in your answers. Only one entry (your first, if you post again or quote someone else and respond, you're out). Of course, after we declare a winner, all bets are off.

Post the question in bold and your answer beneath it in regular text.

[EverythingGolf]

1.When the golf club hits the golf ball, what's required for the ball to go up in the air?

Back spin

2.In a properly struck golf shot, what does the divot tell you?

The direction the club is traveling through impact.

3.What primarily determines the starting direction of the golf ball?

The face.

4.Can you actually compress a golf ball?

Yes.

5.Why is it easier to curve a 4-iron than a sand wedge?

Less loft.

6.What makes a golf ball break?

Speed.

7.How do you increase backspin on a shot? What has to actually happen?

Hit the ball first, make contact with the ball then the ground, make sure the grooves are clean!

8.If you look at any PGA Tour range, almost everyone has a different style of grip, posture, alignment, etc. How are they fundamentals?

Everyone has different style of each.

9.At what point in the swing do the hands reach their lowest point?

Bottom of the swing arc.

10.With a driver, why does hitting up actually make the ball go farther?

Less spin. You want a positive AoA.

[iacas]

1.When the golf club hits the golf ball, what's required for the ball to go up in the air?
Without getting too detailed, positive loft on the clubface while striking the ball below the equator (with an AoA and other impact conditions that's not so severe that it negates it the clubface normal - 1° driver loft with -10 AoA, for example).

2.In a properly struck golf shot, what does the divot tell you?
Not much at all. It can tell you the rough path but only to within +/- 10° or so, and it's after you've hit the golf ball. It can confirm that you managed to hit the ground, too. :)

3.What primarily determines the starting direction of the golf ball?
The clubface normal, even on low spinners with a wedge at 45° spin loft. ;)

4.Can you actually compress a golf ball?
No. You can deform the heck out of one though, but the golf ball does not actually get appreciably denser, no. It's just easier to say "max compression" and whatnot instead of "max deformation." Plus who really wants to say "man you deformed the heck out of that one!"?

5.Why is it easier to curve a 4-iron than a sand wedge?
The decreased spin loft results in more severe tilts to the spin axis for equal horizontal differences in clubface normal and club path (i.e. what Flightscope would report as clubface angle and club path).

6.What makes a golf ball break (putting)?
Gravity.

7.How do you increase backspin on a shot? What has to actually happen?
Increase the spin loft (up to about 45°)! You can do this in three ways: more negative AoA with same dynamic loft, more dynamic loft with same AoA, or more negative AoA and more dynamic loft simultaneously. Assumes the same clubhead speed, contact location on the clubface, etc, otherwise "hit it on the bottom of the driver face" would be an acceptable answer (vertical gear effect), as would "swing faster."

8.If you look at any PGA Tour range, almost everyone has a different style of grip, posture, alignment, etc. How are they fundamentals?
They're fundamentals because they all have a good grip that suits their swing, a good setup, good alignments (for them). However, they are not commonalities. We fix a lot of grips, though, and you've never seen a good player with a lousy grip. The grip (and everything else) has to be functional for that golfer.

9.At what point in the swing do the hands reach their lowest point?
Before the bottom of the swing arc, typically around A6.5 or so, or just in front of the trail thigh (roughly).

10.With a driver, why does hitting up actually make the ball go farther?
Decreased spin loft results in high launch, low spin conditions that maximize carry. Flying through the air is easier than rolling or bouncing along the ground.

[Golfingdad]

When the golf club hits the golf ball, what's required for the ball to go up in the air?

Backspin, the air traveling across the dimples of the ball provide lift.

In a properly struck golf shot, what does the divot tell you?

The hole in the ground will show you the direction the club was traveling right after impact.

What primarily determines the starting direction of the golf ball?

Wherever the clubface is pointing.

Can you actually compress a golf ball?

Sure.  Balls are soft, they go squish when you hit them solidly.

Why is it easier to curve a 4-iron than a sand wedge?

Less backspin, and therefore any sidespin on the ball is a greater percentage of the total and magnifies curve.

What makes a golf ball break?

A sledgehammer?  I didn't watch the video, so I am assuming you mean putting.  I will say gravity makes the ball break.  It always wants to curve downhill.

How do you increase backspin on a shot? What has to actually happen?

I'm going to say you need a steeper angle of attack.  The angle of the clubface in relation to the path it's traveling creates more backspin so the bigger that angle, the more the spin.

If you look at any PGA Tour range, almost everyone has a different style of grip, posture, alignment, etc. How are they fundamentals?

There are a lot of different functional ways to grip the club and if you don't have one that functions, it affects everything else.  Same is true for posture, alignment, stance, etc.  I would also like to point out that fundamental is not a synonym for commonality. Just wish I could remember where I heard that. ;)

At what point in the swing do the hands reach their lowest point?

Immediately after impact.  Right in the middle of the divot.

With a driver, why does hitting up actually make the ball go farther?

It allows you to have a higher launch angle with less backspin.

I should add that some of these answers should have question marks on the end of them because I'm unsure.  But hopefully I pass this test and don't get kicked out of here. :)

[JetFan1983]

1. When the golf club hits the golf ball, what's required for the ball to go up in the air?
2. In a properly struck golf shot, what does the divot tell you?
3. What primarily determines the starting direction of the golf ball?
4. Can you actually compress a golf ball?
5. Why is it easier to curve a 4-iron than a sand wedge?
6. What makes a golf ball break?
7. How do you increase backspin on a shot? What has to actually happen?
8. If you look at any PGA Tour range, almost everyone has a different style of grip, posture, alignment, etc. How are they fundamentals?
9. At what point in the swing do the hands reach their lowest point?
10. With a driver, why does hitting up actually make the ball go farther?

Answers:

1) Lift is created by backspin and the Magnus Effect.

2)

Originally Posted by iacas

Divot Direction

Your divot - the actual piece of dislodged grass - should almost always fly to the left. The clubface closes (even if it's staying relatively square to the arc and closing slowly) and the path of the clubhead goes left, so most divots end up going to the left. Unlike the ball flight laws, divots tend to fly in the direction of the path of the clubhead at the end of the swing. ;-)

But if you want to talk about the hole in the dirt - frankly, I don't know what that's called, so I'll call it the "trench" unless I come up with something better in a few minutes - then that will rarely point to the right except in the rarest of cases (i.e. hooks). There are a few reasons for this, some involving the physics of how a golf club interacts with dirt and grass and your natural swing shape, but let's consider a stock push-draw with a 6-iron. If the player hits down on his six iron 6 degrees, his path will be roughly three or four degrees to the right (and his clubface, if he hits a good shot, will be about 1-2 degrees right of target). The ball is gone, the divot is taken, and the clubhead continues moving in three dimensions - down, out, and forward - to low point about four inches in front of the ball. Then it exits, with the clubhead moving again in three dimensions - forward (duh), up, and in.

In the end, we get a section of a circle - an arc, with roughly equal halves on each side of the low point. Because the total divot length is about six to eight inches, and because the angles will go from about 3 degrees to the right to three degrees to the left, the divot will "point" pretty straight. Have a look at the image to the right - that divot is "pretty straight" and that's with a sudden change in angle, not the smooth arc and rough edges you'd get from a normal fairway divot.

Review my "A-B-C-D-Plane" video for more on this, by the way, but consider the fact that you can hit a dead push as well - clubface and path both 3 degrees right, for example - and have a divot pointing relatively "straight" and also left of where the ball went.

Now, people who cut the ball, their divots most definitely point to the left because, if they're hitting down on the ball enough, they have to shift their baseline far enough left to counter the fact that the clubhead is still traveling down, out, and forward.

Long story short: drawers tend to have relatively straight divots, and faders tend to have divots pointing a fair amount to the left.

Divot Shape

If you're a fan of looking at all of your divots, stop. Look at them generally, but unless you notice a pattern that persists, it's pointless. An individual divot can look "toe deep" or "heel deep" because the ground was different levels of softness or not quite level or a few other reasons. Don't obsess over individual divots.

If you see a pattern that's heel deep or toe deep, though, consider having your lie angles adjusted.

Divot Depth

Though I value tools like Trackman, oftentimes the people who promote Trackman the heaviest get a bit too wound up in them. They'll say that you can't properly diagnose a golfer based on ball flight and video alone. My response to that? You rarely fix a slice by telling the golfer to increase his angle of attack. That's another D-Plane thing, if you're interested...

Anyway, I'll explain what a good divot depth is by explaining the extremes. On one side, you've got the "pickers" of the golf ball. I used to be a picker. I also used to lose the flying wedge and have a shaft very close to vertical at impact. Picking the ball consistently is difficult, particularly with shorter clubs. On the other end you've got the really big diggers. These people have a lot of shaft lean at impact, because the club is still traveling down quite a bit before it gets out of the ground. As you can imagine, it's easier to take bigger divots with your wedge than your 4I, but I've seen some big divots taken with every club. Including my high school teammate Franco taking them with his driver. :-P

The proper divot depth varies by the conditions (wet, firm), the lie (uphill, downhill), the type of shot you want to play, and so on. Let's assume average conditions for all of them and a relatively stock shot. In this case, with a 6-iron, the divot should get through the fairway grass and expose dirt. It'll be the "one piece" type of divot that's on the edge of falling apart (again, given relatively average conditions - and they may vary in your area, because Bermuda divots tend to fall apart more easily in my experience - I'm talking about moist but not wet poa/bent/bluegrass divots). With a wedge the divot will want to stay together a bit more with more dirt, and with a long iron will be mostly grass with the bottom of the club just reaching the dirt. Why? Again, you have more shaft lean with wedges than you do with long irons. With a fairway metal or hybrid? Scuff marks will suffice.

Ball Position

If you play the ball back, you'll tend to take bigger divots than a guy who plays the ball forward. Duh. Right?

Flip and Divot

Can you flip and still take a divot? Though the real answer is "no" it really depends on you defining "flip" the same way I do as well as one other thing. You can flip (i.e. let's say a "flip" occurs if the shaft has passed the left arm prior to impact) yet still drive the clubhead down into the ground if your shoulder alignments and tilts are out of whack. You can also flip and still take a divot with the ball position well back. Think about it.

So no, a divot doesn't mean that you didn't flip.

3) The club face

4) Yes.

5) It's extremely difficult to tilt the spin axis on a sand wedge.

6) In order of "most important factors" or "biggest influence."

A) Slope Amount

B) The length of the putt

C) Angle to the slope

D) Stimp

E) Ball Speed

F) Grain

7)

Originally Posted by iacas

As to the dynamics of impact with higher lofted clubs, here's what happens.

The ball slides up the clubface but it's a relative thing - the clubhead is going down. The ball is only ever going upwards and forwards - it's never going "down" unless you top it. The clubface - the dynamic loft - is still "more important" than the path of the club (downward), so the ball never goes down. As the clubface goes down and forward, the ball is going up and forward. The grooves on higher lofted clubs help to grab the ball and you effectively generate a system like two gears - the back of the ball meshes with the "gears" on the clubface, and both go "down." This creates backspin.

Maximum backspin is caused when the ball grips the clubface the most, when the ball is halfway through the impact interval and at max compression. The CG of the ball projected onto the clubface will often be a groove or so higher than the initial impact point, again because not only is the ball moving upwards, but the clubhead is moving downwards.

So yes, the ball moves up the clubface during impact, but I don't know that I'd call it "rolling" up the clubface per se. If you had a ball that didn't "compress" at all, you'd get virtually no spin on the ball at all. That compression is why urethane balls (softer cover) spin more around the greens than surlyn balls - the softer outer cover is all that can "compress" against the clubface on short shots without a lot of clubhead speed.

8) They are variables, generally chosen by the golfer -- either consciously or unconsciously -- to promote a certain shot pattern. They are incredibly important, but they are not "fundamental" in that one grip or one alignment doesn't work for everyone.

9) The hands reach low point directly beneath the center of their rotation, which would be directly below the spine, or the center of the shoulder blades.

Marked with a dot in the image on the left, below:

10) I think because launch angle and backspin rates tend to improve with a slightly positive angle of attack with driver.

[Phil McGleno]

1.When the golf club hits the golf ball, what's required for the ball to go up in the air? The ball cannot take off if the player is standing on a conveyor belt that matches the clubhead speed in the opposite direction. 2.In a properly struck golf shot, what does the divot tell you? That unlike 98% of women golfers you're capable of hitting the ground. 3.What primarily determines the starting direction of the golf ball? The location of the nearest body of water or sand. 4.Can you actually compress a golf ball? I don't know, but I know I can compress my nuts trying to squeeze into some Ian Poulter pants. No wonder that guy's got such a sour disposition. 5.Why is it easier to curve a 4-iron than a sand wedge? Because God has a ****ed up sense of humor. 6.What makes a golf ball break? Usually a mower running over it will do. 7.How do you increase backspin on a shot? What has to actually happen? First, you get a conveyor belt... 8.If you look at any PGA Tour range, almost everyone has a different style of grip, posture, alignment, etc. How are they fundamentals? Is that the new show with Lucy Liu? 9.At what point in the swing do the hands reach their lowest point? When they're reaching into your back pocket to pay off your bets. 10.With a driver, why does hitting up actually make the ball go farther? Because hitting up always makes the ball go farther than screwing up.

[mchepp]

Jetfan nicely done. Some serious homework there.

For #4 I want to know what is meant by "compress" I think we need a slightly better definition than to say compress.

I am interested to see what the answers for #9 and #10 will be. If I were to answer I would say for #10 'because Trackman told me so'.

Edited to add answers:

1.When the golf club hits the golf ball, what's required for the ball to go up in the air?
Backspin.

2.In a properly struck golf shot, what does the divot tell you?
The golfers low point.

3.What primarily determines the starting direction of the golf ball?
85% face angle for the driver

4.Can you actually compress a golf ball?
Because compress is so poorly defined, I will say no. But I don't like the question

5.Why is it easier to curve a 4-iron than a sand wedge?

A sand wedge has more backspin and therefore it is harder to tilt the spin axis.

6.What makes a golf ball break?

Gravity

7.How do you increase backspin on a shot? What has to actually happen?
This is another question that is vague. I could increase the depth of my groove on the club and increase the backspin amongst other things.

8.If you look at any PGA Tour range, almost everyone has a different style of grip, posture, alignment, etc. How are they fundamentals?
Golf instruction has confused commonality with fundamental. A good functional grip is a requirement to good golf. If you are aligned 90 degree to the target you will not play good golf, so there is some functionality required in each of the GASP's.

9.At what point in the swing do the hands reach their lowest point?
For a good golfer the right leg (right handed golfer)

10.With a driver, why does hitting up actually make the ball go farther?
Because Trackman says so

[iacas]

Originally Posted by mchepp

Jetfan nicely done. Some serious homework there.

And yet the contest isn't over... ;)

Originally Posted by mchepp

For #4 I want to know what is meant by "compress" I think we need a slightly better definition than to say compress.

Watch the video. That's all you get. And you used your entry to not post any answers? Booo! :)

[dkmago]

1. When the golf club hits the golf ball, what's required for the ball to go up in the air?
2. In a properly struck golf shot, what does the divot tell you?
3. What primarily determines the starting direction of the golf ball?
4. Can you actually compress a golf ball?
5. Why is it easier to curve a 4-iron than a sand wedge?
6. What makes a golf ball break?
7. How do you increase backspin on a shot? What has to actually happen?
8. If you look at any PGA Tour range, almost everyone has a different style of grip, posture, alignment, etc. How are they fundamentals?
9. At what point in the swing do the hands reach their lowest point?
10. With a driver, why does hitting up actually make the ball go farther?

1) The club has to hit the ball below the equator of the ball relative to the slope of the lie.  For example, a ball (on a 2 degree uphill slope) hit with a forward leaning 3 iron having a 3 degree effective loft AND with a 3 degree positive angle of attack hit just below the equator of the ball will go up in the air with no spin.

2) If your clubs are property fitted?

3) Club face because golf balls are harder nowadays and don't ride on the club as long as they used to

4) Yes

5) Becuase the  curve is a result of the difference between side spin and back spin.  The 4 iron imparts less back spin allowing for more curve than a sand wedge.

6) A golf ball breaks primarily because of gravity.

7) To increase backspin on a ball you must increase the difference between the loft and the angle of attack.

8) These are the factors that allow you to hit repeatable shots?

9) Just before impact on a driver when you want a positive angle of attack and at or after impact on an iron where you want to increase backspin.

10) Hitting up with a driver makes the ball go farther because it decreases the difference between the loft and the angle of attack, thereby decreasing backspin.

[iacas]

Please try to follow the prescribed answer format. Still no winners. Contest closes at midnight Eastern time tonight.

[Fried Egg]

When the golf club hits the golf ball, what's required for the ball to go up in the air?

Positive loft applied at or below the ball's CoG.

In a properly struck golf shot, what does the divot tell you?

Not much. You can have a divot going to the left and still hit a push draw (for a righty).

What primarily determines the starting direction of the golf ball?

Face angle.

Can you actually compress a golf ball?

By definition, possibly slightly. Deformation is probably more accurate.

Why is it easier to curve a 4-iron than a sand wedge?

When the spin loft is lower, it is easier to tilt the spin axis. Hence, easier to curve less lofted clubs.

What makes a golf ball break?

Gravity.

How do you increase backspin on a shot? What has to actually happen?

Lessen spin loft. Lessen the difference between the dynamic loft of the club and the angle of attack. Usually done by maintaining loft and shallowing AoA. This also increases the friction between the ball and club, adding backspin.This is why hitting down more usually doesn't increase spin. Generally, the increased AoA is offset by a decreased dynamic loft when hitting down, keeping the spin loft the same.

If you look at any PGA Tour range, almost everyone has a different style of grip, posture, alignment, etc. How are they fundamentals?

They are fundamentals to the point where to hit the ball solidly, consistently at your target, and far enough, everyone needs to grip the club, set up to the ball, and align themselves in a way that will allow this. Although, there can be great varitions of each fundamental that will allow this to happen.

At what point in the swing do the hands reach their lowest point?

They reach their low point around the back leg/close to the center of the sternum. They then rise to and through impact.

With a driver, why does hitting up actually make the ball go farther?

It increases the launch angle and lessens the amount of spin.

[boogielicious]

1. When the golf club hits the golf ball, what's required for the ball to go up in the air?    -  The angle of the club face has to be > 90 degrees to the ground at impact.

1. In a properly struck golf shot, what does the divot tell you?  - whether you have hit the ball first before the ground.
2. What primarily determines the starting direction of the golf ball?  - the club face direction at impact.
3. Can you actually compress a golf ball? - A tiny amount.  It is more of an elastic collision.
4. Why is it easier to curve a 4-iron than a sand wedge? -  less backspin as compared to a wedge.  Gyroscopic and aerodynamic effect of backspin is less compared to side spin.
5. What makes a golf ball break? - Gravity.  The ball will break downhill on a putt.
6. How do you increase backspin on a shot? What has to actually happen?  - Better contact with forward leaning shaft at impact
7. If you look at any PGA Tour range, almost everyone has a different style of grip, posture, alignment, etc. How are they fundamentals? - They are not.  Fundamentals are: Steady Head, Weight forward at impact, flat left wrist at impact, diagonal sweet spot path, club face control.
8. At what point in the swing do the hands reach their lowest point?  - Under the forward armpit.
9. With a driver, why does hitting up actually make the ball go farther? - Higher launch angle and less backspin allow for more carry.  This doesn't include roll after hitting the ground.

[iacas]

Down to the last few hours.

Yes, it's a quiz that's more for instructors. Knowing the answers won't directly help you play better golf. Some are worded a little weird.

But have some fun with it and post your answers. Time's runnin' out. :)

[Jhwarren]

When the golf club hits the golf ball, what's required for the ball to go up in the air?

Any amount of positive dynamic loft

2.   In a properly struck golf shot, what does the divot tell you?

Nothing

3.   What primarily determines the starting direction of the golf ball?

Clubface at impact

4.   Can you actually compress a golf ball?

No. There is no reduction in actual mass of the ball. The shape is simply altered.

5.   Why is it easier to curve a 4-iron than a sand wedge?

A 4 iron produces more sidespin than backspin, vice versa for sand wedge

6.   What makes a golf ball break?

Factors that affect break are: length of putt, angle of path relative to the zero line, uphill or downhill,

speed of the greens, and the slope

7.   How do you increase backspin on a shot? What has to actually happen?

Factors that increase backspin: Spin Loft, Clubhead speed and contact location

8.   If you look at any PGA Tour range, almost everyone has a different style of grip, posture, alignment, etc.

How are they fundamentals?

There are only fundamentals if we take the definition "something that is essential or necessary."

Everyone has to have a grip, stance, posture, etc. of some sort.

9.   At what point in the swing do the hands reach their lowest point?

Center of rotation

10.   With a driver, why does hitting up actually make the ball go farther?

Increases launch angle and decreases spin. The ball flies further and rolls out

[birlyshirly]

1. When the golf club hits the golf ball, what's required for the ball to go up in the air? A point of impact between clubface and ball somewhere on the ball's lower half. AKA positive dynamic loft.
2. In a properly struck golf shot, what does the divot tell you? It tells you where your club went AFTER impact, but it's hard to tell much in enough detail to diagnose a swing fault.
3. What primarily determines the starting direction of the golf ball? In 3D, the normal to the clubface at impact, or more precisely, the moment of maximum deformation of the ball.
4. Can you actually compress a golf ball? No. The ball deforms, but does not compress.
5. Why is it easier to curve a 4-iron than a sand wedge? Curve results from a tilted spin axis. The spin axis will align at 90* to the "d plane" formed by the clubface normal and clubhead path. The wider the angle (measured within the D-plane) between the clubface normal and path (AKA "spin loft"), the greater will be the amount of tilting of the d-plane and hence the ball's spin axis, for any given misalignment (say 2*) between the horizontal orientation of the clubface normal and the clubpath.
6. What makes a golf ball break? Gravity will pull a ball in a downhill direction across any slope on which the ball is rolling.
7. How do you increase backspin on a shot? What has to actually happen? Backspin increases with spin loft and/or clubhead speed and/or vertical gear effect from a "low blow", although the extent to which the last is a real and substantial effect is moot.
8. If you look at any PGA Tour range, almost everyone has a different style of grip, posture, alignment, etc. How are they fundamentals? Schoolboy rhetoric. Sorry, this spoils an otherwise good set of questions. You could write a long essay on what "fundamental" means in golf, but it only has meaning within a system of teaching or performance (and the meaning can change according to the system). Does that disqualify the use of the term? Maybe. Are those listed the only fundamentals? No. Could you mess with a good player's fundamentals and not affect their ballflight? No. Can some fundamentals be more important than other fundamentals? Not without stripping the term of meaning.
9. At what point in the swing do the hands reach their lowest point? Roughly opposite the trailing thigh prior to impact.
10. With a driver, why does hitting up actually make the ball go farther? If it does, you're playing too little loft in your driver. But hitting up allows you to play a driver with less loft than would be optimal for a 0* AoA or a downward hit, which in turn will decrease spin loft, which will increase ball speed, which given an optimal launch angle, will increase distance.

[Jhwarren]

Just a side note, I would like to thank Mario for putting this together and especially iacas for bringing this to my and other's attention. I'm sure I didn't get all the questions correct, but this thread made me do some research, really think about fundamental questions to what is actually happening in the golf swing ( no pun intended toward question #8 ), and grow as a student of this game. I would love to see future threads similar to this one. Can't wait until the answers are revealed at midnight.

[tkahlm]

1. When the golf club hits the golf ball, what's required for the ball to go up in the air?

Backspin otherwise the ball won't fly.

2. In a properly struck golf shot, what does the divot tell you?

The divot is almost completely worthless. It is hard to tell if the lie angle is incorrect because it would only be by a degree or two.

3. What primarily determines the starting direction of the golf ball?

Club Face angle is about 85%

4. Can you actually compress a golf ball?

Yes

5. Why is it easier to curve a 4-iron than a sand wedge?

Less loft makes it easier to change the spin axis tilt.

6. What makes a golf ball break?

Speed primarily

7. How do you increase backspin on a shot? What has to actually happen?

Getting a higher spin loft.

8. If you look at any PGA Tour range, almost everyone has a different style of grip, posture, alignment, etc. How are they fundamentals?

No fundamentals not one looks for all.

9. At what point in the swing do the hands reach their lowest point?

At the bottom of the swing arc.

10. With a driver, why does hitting up actually make the ball go farther?

It creates less spin on the golf ball and a better launch angle.

[Adam Young]

Ok, I'm going to have a go - although I'm nervous as hell, so be gentle with me Erik :)

• When the golf club hits the golf ball, what's required for the ball to go up in the air?

the contact point of the clubhead and ball must be below the equator of the ball relative to the angle of attack

• In a properly struck golf shot, what does the divot tell you?

point of contact with the ground

• What primarily determines the starting direction of the golf ball?

clubface

• Can you actually compress a golf ball?

between clubface and turf - no.    does the ball compress on the clubface? yes

• Why is it easier to curve a 4-iron than a sand wedge?

I'm finding this very difficult to word, as I understand the higher lofted club actually have more curve if the lie angle is incorrect.

I'm going with "because there is less loft on a 4 iron, so the spin axis is more easily tilted if the face/path combo is not matched"

• What makes a golf ball break?

What I consider the easiest question, although will probably get this one wrong for that reason. - Gravity

my alternative answer is Einstein's theory of general relativity (although go with my first one)

• How do you increase backspin on a shot? What has to actually happen?

striking the ball first increases spin compared to someone who gets too much grass inbetween face and ball.

Increase the speed of the clubhead and the spin rate will also increase further.

Increase the difference between loft and angle of attack (spinloft) and (to a point) the spin will increase.

Strike the ball from below the centre of mass of the clubhead and vertical gear effect will increase spin

increase frictional coefficient of the clubface and spin will increase

• If you look at any PGA Tour range, almost everyone has a different style of grip, posture, alignment, etc. How are they fundamentals?

they are not - they are just dogma

• At what point in the swing do the hands reach their lowest point?

ooh, interesting. Different for everyone. There are simply too many variables and moving parts to define one universal point. You would also only be able to truly identify this with 3D and not with stills

• With a driver, why does hitting up actually make the ball go farther?

Twofold

It tends to produce a lower spinloft for maximal compression of the ball thus maximising energy transfer

it produces an optimal trajectory through launch conditions

caveat - hitting MORE up on the ball does not always produce more distance. There are optimal launch conditions for each clubhead speed